1. Field of the Invention
This invention relates to a process for stabilizing 2,3-dichloro-1,3-butadiene against polymer formation.
2. Description of the Prior Art
2,3-Dichloro-1,3-butadiene is a well known monomer which is easily polymerizable, and polymers thereof are disadvantageously formed in the manufacture, distillation, or storage of the monomer.
These polymers are undesirable because they are usually insoluble and adhere to the apparatus used for the manufacture or treatment of the monomer, resulting in the clogging of conduits and other parts of the apparatus. This clogging causes difficulty in the operation of the apparatus, which is a serious industrial disadvantage.
Also, the formation of the polymer in the storage of the monomer causes an undesirable decrease in the purity of the 2,3-dichloro-1,3-butadiene monomer.
2,3-Dichloro-1,3-butadiene is generally not used alone but is generally used to form copolymers together with other monomers such as 2-chloro-1,3-butadiene. Before the 2,3-dichloro-1,3-butadiene monomer is used, any precipitated polymers of 2,3-dichloro-1,3-butadiene formed in storage have to be removed. The polymers have been removed by redistillation. However, the redistillation of the monomer before use is a difficult operation because of the ease with which the monomers are polymerized. When a large amount of the monomer is required, the redistillation becomes practically impossible.
If the monomer containing these polymers is used without separation of the polymers, the undesirable polymers adhere to the polymerization apparatus to cause an adverse effect on the property of the resulting product. Accordingly, the inhibition of the formation of polymers from 2,3-dichloro-1,3-butadiene monomers remains in need of a solution. One attempted solution for inhibiting the polymerization of 2,3-dichloro-1,3-butadiene requires the refrigeration of the monomer with the addition of t-butyl catechol. Another attempted solution includes the addition of a piperidine derivative to the monomer. However, satisfactory results have not been obtained by these conventional methods. Accordingly, a need therefore exists for a process to stabilize 2,3-dichloro-1,3-butadiene from polymerizing.